Purpose The purpose of this study is to analyze the impacts of different policies to address the water supply crisis experienced by the metropolitan region of Sao Paulo during 2013 to 2015 and evaluate the resilience of its water supply system for the coming years. Design/methodology/approach The methodology used in this study is based on the system dynamics simulation paradigm, combined with empirical data obtained from the regional water authority. Findings The results from the simulations suggest that the first layer of sustainability of the water supply in the region strongly depends on how the system’s operator responds to crises, in particular how it balances policies acting on the supply and demand for the resource. Practical implications Severe water crises typically make salient the perception that water is a finite and public resource. Long-term, sustainable management of the system requires a paradigm shift from widespread, old-fashioned beliefs that water is an infinite resource. It also requires active management to increase the system’s preparedness to withstand events caused by climate change. Originality/value This study contributes to the system dynamics and water resource management literature by presenting an integrative model to evaluate the resilience of a particular water supply system. Although there are previous studies on this subject, the present one focuses on the role that the water authority plays in a crisis and especially on a specific combination of policies to address an episode of crisis in a system unprepared for it.

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Purpose This paper aims to understand and explore the causal relationship of elements responsible for the macro vicious cycle of poverty in Guinea-Bissau, and discuss policies to break it. Design/methodology/approach The methodology used in this study is based on the system dynamics simulation paradigm. Findings Breaking the Guinean poverty cycle requires a multifaceted approach involving more resources and the building of several national capabilities. Traditional approaches tend to fail. Research limitations/implications Limitations come from the level of abstraction used in the model, which does not detail the processes for building specific capabilities and their interrelationships, and the necessary exclusion of variables that may have an impact in the process. Considering implications, the study models the evolution of human development index (HDI) in Guinea-Bissau, linking it to the economy and political sectors and allowing the simulation of different scenarios. Practical implications The study presents a critical stance towards common recommendations from international agencies, and it provides a blueprint for development of more effective public policies. Social implications Overcoming the poverty trap in sub-Saharan countries remains a challenge for the international community. The study aims at helping in the process of integrating different frameworks into a compact and manageable model. Originality/value The study contributes to the system dynamics and economic development literatures by presenting an integrative model of human development in Guinea-Bissau. There is no study in the system dynamics literature modelling the relationship of HDI to economy and political sectors while different and contradictory points of view characterize the economics literature, leaving well-meaning public officials in Guinea-Bissau at a loss of mental models to tackle the poverty trap in the country.

Purpose The purpose of this paper is the development of a framework to address complex social problems. The paper proposes an integrative framework inspired in complexity sciences, using it to explain the demise of cigarettes in recent decades. Design/methodology/approach The paper uses the method of system dynamics to represent the complexity inherent in most social ecosystems where social marketers operate. Findings The framework identifies the major determinants of complex problems in social ecosystems, giving emphasis to the role performed by endogenous social structures. The paper presents the results of a simulation replicating the evolution of perceived attractiveness of cigarettes in recent decades, highlighting the role of the Surgeon General’s 1964 report in the USA as a catalyst force that accelerated the process of change. Research limitations/implications The limitations derive from the use of the system dynamics method, in particular the high level of aggregation of variables. Implications include the potential for increased cross-fertilization between social marketing and other disciplines concerned with social change. Practical implications The eight elements that compose the proposed framework can be identified or applied to any social ecosystem, helping in the identification of points with high leverage for social change. Social implications Proper understanding of how complex social problems arise is vital to increase the odds of success of social marketing interventions. The paper also highlights common threads in the development of problems in different social ecosystems. Originality/value The paper presents a novel framework for addressing the complexity inherent to the social ecosystems where social marketers operate.

It is recognized that the world maritime industry has a cyclical behavior. Shipowners face periods of fabulous profits and disastrous miscalculations. The object of this work is to investigate the nature and causes of such behavior. The maritime industry is a complex system that can be split in four main markets: freight; secondhand ship; new ships and ships for demolition. The influences of one part on the others are not always well understood. Although the world economy influences the maritime industry, it has been observed that its behavior is fundamentally endogenous, such as: its own structure; the relationships between its parts; and the process of decision making. Furthermore, this behavior has strong dynamic characteristics. System Dynamics has been proving to be a suitable tool for analyzing such systems and, therefore, has been chosen. In this method a mathematical model is developed from a functional and causal description of the real system. A preliminary model was formulated which include three main sectors of industry: financial, freight market and shipbuilding industry. These sectors cover most of the relevant interactions and determinants of the behavior. The model simplified from the real world in many instances, and is based on certain assumptions previously stated. In spite of the simplifications, assumptions and omissions, the behavior of the model, as shown in computer results, replicates the most fundamental characteristics of the real world, the historical trends chosen as reference modes. It has been observed that the new ships ordering decisions are extremely important in stimulating the cyclical behavior. In this preliminary work this decision is founded on demand forecast and expected profitability of shipowners. This profitability is assumed as a function of shipowners total costs and a rate of return of investment, assumed as 15%. viii The model developed herein can serve as foundation structure upon which to develop more fully this area of investigation, and as a guide in such developments. It is hoped that further work is carried out towards gaining a sounder understanding of the maritime economics market cycles. Considering the results presented so far, it is possible to conclude that System Dynamics is a valid tool for investigation and can yield rewarding results.